The present invention relates to a method and an apparatus for removing particles from a surface of an article, such as a semiconductor wafer in a clean room, a reactor for coating a surface of a semiconductor device and its peripheral equipment, and a glass for liquid crystal.
A clean room is used to produce semiconductor devices and like, and is required to be free of particles such as dust so as to provide a surface of a semiconductor wafer free of particles. Recently, it has been required, for example, to remove particles from a semiconductor wafer having a dimension as small as several micrometers and preferably particles having a dimension smaller than one micrometer.
A conventional method for cleaning particles from a surface of an article includes a contact process and a non-contact process, as shown in FIG. 8. The contact process includes a fixed brush vacuum process and a rotating brush vacuum process. Both of the contact processes allow the removal of particles having a dimension of not less than scores of micrometers, but does not remove particles having a dimension of up to scores of micrometers.
The non-contact process includes a vacuum process, an air knife process, and a ultrasonic air process. The vacuum process removes particles having a dimension of not less than about 100 micrometers, and the air knife process does not enable the removal of particles having a dimension of not more than scores of micrometers. The ultrasonic air process allows the removal of particles having a dimension as small as several micrometers. However, the ultrasonic air process does not enable the removal of particles having a dimension of not more than 1 micrometer.
The present inventors have proposed removing particles from a wafer by irradiation with an ultraviolet ray, a radiation ray and a laser ray onto a wafer, thereby emitting a photoelectron therefrom so as to remove the articles therefrom (please refer to JP-A-4-239,131 and JP-A-6-296,944). However, a surface of a wafer is directly irradiated by an ultraviolet ray, a laser ray, or a radiation ray in this process. Therefore, if a surface of the wafer is sensitive to these rays, the wafer surface may undergo an unfavorable chemical reaction, thereby limiting its application.